WASHINGTON — Rudy Giuliani has delivered a political shot-in-the-gut to President Obama, charging the president doesn’t “love America.”

“I do not believe, and I know this is a horrible thing to say, but I do not believe that the president loves America,” Giuliani told about 60 conservative business leaders gathered Wednesday night at the 21 Club to hear Wisconsin Gov. Scott Walker.

According to the former mayor, Obama doesn’t love Giuliani either.

“He doesn’t love you. And he doesn’t love me. He wasn’t brought up the way you were brought up and I was brought up, through love of this country,” he continued, as Walker, who has entered the top tier of Republican presidential candidates, sat nearby.

The comments are a departure from standard political rhetoric, where blasting someone’s ideas is considered fair game, but questioning an opponent’s love of country is usually a no-no. Politico reported the expansive comments.

Giuliani elaborated on “Fox and Friends” Thursday morning.

“Well, first of all, I’m not questioning his patriotism. He’s a patriot, I’m sure,” he said on the program. “What I’m saying is, in his rhetoric, I very rarely hear the things that I used to hear Ronald Reagan say, the things that I used to hear Bill Clinton say about how much he loves America.”

Giuliani’s language at the dinner riffed off a more common attack made by others: that Obama doesn’t believe in “American exceptionalism.”

“With all our flaws, we’re the most exceptional country in the world. I’m looking for a presidential candidate who can express that, do that and carry it out,” Giuliani continued. “And if it’s you, Scott, I’ll endorse you. And if it’s somebody else, I’ll support somebody else.”

Giuliani told Politico afterward: “What country has left so many young men and women dead abroad to save other countries without taking land? This is not the colonial empire that somehow he has in his hand. I’ve never felt that from him.”

He then blasted Obama for failing to explicitly condemn Islamic extremism.

“I thought the Crown Heights riots were a pogrom because you’re going out trying to kill Jews,” he said. “Why is this man incapable of saying that? You’ve got to be able to criticize Islam for the parts of Islam that are wrong.”

The former mayor also referenced Obama’s recent remarks at a National Prayer Breakfast, when he invoked the “terrible deeds” of the Crusades and Spanish Inquisition to make the point that Christians, not just Muslims, have killed in the name of faith.

“You criticize Christianity for the part of Christianity that is wrong. I’m not sure how wrong the Crusades are. The Crusades were kind of an equal battle between two groups of barbarians. The Muslims and the crusading barbarians. What the hell? What’s wrong with this man that he can’t stand up and say there’s a part of Islam that’s sick?”